DISEASES OF THE SKIN. 329 



DISEASES OF THE SKIN. 



The structure and functions of the skin have already 

 (page 117) been considered, as well as the reasons why 

 disorders of this region are so frequent in the dog. Dis- 

 temper, parasites, and skin diseases are the bane of all 

 large kennels of dogs, and with the greatest care they will 

 occasionally occur, while in the absence of especial pre- 

 cautions a kennel may be demoralized if not destroyed. 

 Diseases of the skin are not usually of themselves fatal, 

 but they may so undermine a dog's constitution that he 

 becomes the victim of some fatal malady. 



We wish once more to insist on the close connection 

 between derangements of the digestive organs and of the 

 skin, to be explained reflexly as well as by the deteriora- 

 tion of the blood by poisons introduced from the alimen- 

 tary tract through imperfections in the digestive processes. 



Skin diseases may be divided into parasitic and non- 

 parasitic, but in any case they all, sooner or later, become 

 inflammation of the skin ; and it is from this point of view 

 that they are most profitably studied and treated. 



Instead of considering the numerous phases of cutane- 

 ous inflammation as so many separate diseases, it is much 

 more simple, rational, and, we think, practical, to consider 

 the causes and treatment of inflammations of this great 

 organ as a whole. 



Causation. Inflammation is a perverted nutrition 

 (metabolism) of a part, and its symptoms are the same in 

 the skin as elsewhere, but modified by the fact of exposure 

 to the atmosphere, etc. The cause is external or internal 

 irritation. 



